The M-497 (nicknamed Black Beetle) was an experimental jet-powered locomotive developed and tested in 1966 in the USA. Two second-hand jet engines were mounted atop an existing Budd Rail Diesel Car body which had received a streamlined front cowling. The construct was then successfully sent on test runs over the existing but otherwise unmodified track chosen for its arrow-straight layout and good condition. The car reached a speed of 183.68 mph (295.54 km/h), which is still the light-rail speed record for the United States.Source: http://en.wikipedia.org/wiki/M-497_Black_Beetle